* * * THE UMBELLIFERAE FAMILY * * *
A large, important, succesful family of herbs, sharing an easily identifiable common characteristics, their famous upside down ‘Umbrella flowers’ on stalks, which fill our hedgerows and bridleways with an abundant profusion of summer colour. They have provided us with our most famous root crops, vegetable and medicines, saving & sustaining millions of human and animal lives. They do have a darker side, many are poisonous, fortunately few deaths occur now. Most are native, and common, having colonised every habitat in Britain, bar upland moors, salt marshes & deep shade. Some, introduced by the Romans, have become naturalised and common here, fewer are casuals and garden escapes. They are generally well known for being indistinguishable from each other, but with reference to habitat, flowering time, leaf shape and aroma they can be easily identified.
* * * CLASSIFICATION * * *
The family Umbellifers belongs in the Umbellales order. A large worldwide family containing 3000 species in 400 genera, concentrated in the N Northern temperate region. They are herbs, but Bupleurum has a number of shrubby species, woody members occur in Africa, the largest is Steganotaenia, a 12m high tree. The family contains sub families Apioideae, which contains 9096 of species. Saniculoideae & Hydrocotyloideae, hold the others. There is much overlap regarding diagnostic characteristics, and so each genera usually contain one species, and are said to be monotypic. A concise ‘History of Classification’ is given by Lincoln Constance, 1971.
* * * IDENTIFICATION * * *
Is much easier than previously thought. First consider its habitat, and flowering time, then
the presence or absence of bracts, the number and length of the rays, the shape and degree of dissection of the leaves, aroma is important too. If picking for culinary or medicinal reasons, please refer to a specialist, as plants can be deformed, or mistaken, and result in illness or death if consumed incorrectly, for which actions, the author takes no responsibility. For truly accurate identification, seeds must be seen under a microscope,
or the nucleic chromosomal number established.
* * * POLLINATION * * *
The umbels are unique in their floral uniformity. They encourage free pollination
by unspecialised pollinators, an interesting evolutionary adaptation. The effects of
this promiscuous pollination allow it to increase its natural distribution, and thus
colonise new habitats easily.
The majority of insects are attracted by the copious quantities of nectar, which is
prolonged when the stigmas become receptive, some time after the anthers have ripened. The styolopodium is also often large and brightly coloured, attracting by sight. In others,
the outer petals found on the peripheral rim, are larger, and said to radiate, the inner
disc may have smaller petals, and be coloured yellow, or purple, thus giving the effect
of a single composite flower. This acts as a decoy for insects that might not normally
visit umbellifereae.
2-300 pollinators and visitors have been recorded, the commonest being Diptera, (flies gnats, thrips, mosquitoes) smaller Coleoptera beetles, and Hymenoptera, (ants and small tonuged bees) In a few species, the basal half of the infolded petal is erect and forms a corolla tube it limits access to short tongued Hymemnoptera.
There are usually male flowers in lateral umbels, below the terminal hermaphrodite
umbel. The hermaphrodite flowers contain an extra pollen reservoir, ensuring the success
of these early flowering parts to pollinate. The male flower’s later, ensuring outbreeding
& discouraging self pollination.
* * * SEED DISPERSAL * * *
Hooked spines on many fruits act as a special aid for dispersal by mammals. Others
have broad lateral wings, for dispersal by the wind. The aquatic species have fruits
with hollow spongy interiors, allowing them to float.